| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Multi-Principal Element Alloys IV: Mechanical Behavior
|
| Presentation Title |
Measuring the Entropy of High Entropy Alloys |
| Author(s) |
Kyle Hunady, Elena Priesen Reis, Brent Fultz |
| On-Site Speaker (Planned) |
Kyle Hunady |
| Abstract Scope |
The temperature stability of high entropy alloys is often attributed to their high configurational entropy, which increases with the addition of more elements. However, the impact of these additions on vibrational and electronic entropy remains unclear. We obtained these entropy contributions from heat capacity measurements (2K to 400K) for the 4-component base alloy CoCrFeNi and the 5-component Al-alloys Alx(CoCrFeNi)100-x using a PPMS from Quantum Design. Our findings reveal that equiatomic Al addition (AlCoCrFeNi, or x=20) induces a phase transition from FCC to BCC where the measured loss in vibrational entropy from the structural change (-0.43 kB/atom) exceeds the gain in configurational entropy from adding Al (+0.22 kB/atom). Meanwhile, at lower Al concentrations (x=5), the alloy retains the FCC structure of the base alloy and shows only a minor change in vibrational entropy. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, |